Load information?

[ranmcc]

I have a 20ga Fox Sterlingworth Utica in excellent condition shipped in 1936 with a 1933 serial number. Apparently the barrels were bored out Cyl and IC. The letter says M and F. I had the chambers measured and they are 2 3/4. Can I shoot higher power shells in this gun than the RST I have been shooting? Or should I stay with the lower powered 1100psi shells?

[Researcher]

While no one can tell you over the internet what loads may or may not be safe or appropriate in a given gun, the 2 3/4 inch 20-gauge, progressive burning powder, high velocity, 1 ounce loads, like the Western Cartridge Co.'s Super-X, had been on the market for well over a decade when your gun was made. Most of my 20-gauges have digested some Super-X type cartridges when I believed the situation called for it. One needs to apply some "common sense" to these kinds of things. I briefly had a little Fox 20-gauge, that must have been pretty close to the minimum weight they made, and it got limited to 3/4 ounce 2 1/2 inch Lyalvale cartridges.

[ranmcc]

I am not interested in shooting high powered shells probably would go no higher than 1200psi on the box.

[Twice Barrel]

Your Fox was built strong and undoubtedly can handle modern ammunition which is loaded to a SAMMI max pressure of 11,500 psi, however, recoil is of greater concern due to the 75 year old wood. To be on the safe side I would limit my choice of ammunition to 7/8th ounce loads at 1150 fps and chamber pressure in the 9,500 psi range to stay below a recoil force of 15 ft lbs.